Water Pump Runs Constantly

[Carl n Susan]

The water pump has been working fine at stops along the way. Last night we were at full hookups and I took the opportunity to fill the fresh water tank. I switched the "Fill" valve back to "normal" once I saw water coming out the overflow.

Today when we stopped and used the water pump it continued to run as long as it was turned on. There was a bit of water being pumped out but definitely not the normal level.

I am thinking the check valve is the problem but I am not sure what else might cause the problem. I plan to pull it out tomorrow and see what I can find.

Any ideas you have as to a cause would be appreciated.